jsp登录界面csdn（jsp登录界面下拉列表）
更新：2022-11-16 20:44
本文目录一览：
用jsp怎样做一个用户登录界面
<%@ page pageEncoding="utf-8" contentType="text/html; charset=utf-8" %>
<body>
<h1>Register</h1>
<hr />
<form action="login" method="post">
用户名：
<input type="text" name="username" id="text" />
密码：
<input type="password" name="pwd" id="text" />
<input type="submit" value="登录" id="button" />
</form>
</body>
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
public class AddUser extends HttpServlet {
public void service(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html;charset=utf-8");
request.setCharacterEncoding("utf-8");
String username = request.getParameter("username");
String pwd = request.getParameter("pwd");
try {
if (username.equals("name") && pwd.equals("pwd")) {
System.out.print("登录成功");
} else {
System.out.print("error");
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
简单的登录界面，不需要数据库，如果要链接数据库就要判断很多了。
我想问一下，用JSP如何实现像CSDN主页右上角那种，登录前显示“你还未登录”，“登陆”“注册”登陆后显示
放两个 div，一个里面写“你还未登录”，另一个里面写“登录|注册”，至于链接自己加，然后 div 的 display 都设置成 none，在登录的 servlet 或者 action 中，登录成功后，向 request 里放入 islogin 属性，这样写：
request.setAttribute("islogin", "true");
然后在页面写个 js，接收 request 中的属性 islogin，js 中这样写：
var islogin = "${requestScope.islogin}";
然后判断这个属性，如果 islogin == ""，则没有登录，第一个 div 设置 display: block，如果 islogin == "true" 就显示第二个 div。
JSP编写一个登陆界面
- 首先准备 Dreamweaver8 软件，解压安装。如下图所示：点击安装程序，然后输入序列号就可以了。
- 在安装软件时候，我们可以看到是否关联【jsp文件】。
- 安装好了软件以后，我们打开 Dreamweaver8 软件。点击菜单上的【文件】——【新建】。
- 弹出【新建文档】——【动态页】——【jsp】——【创建】。
- 点击【拆分】，在【body】标签下面输入：
<% out.println("Hello World！"); %>
- 然后按快捷键【Ctrl+S】保存 jsp 文件。保存类型 jps。
jsp登陆界面源代码
1. login.jsp 文件
<%@ page language="java" contentType="text/html; charset=GB18030" pageEncoding="GB18030"%>
<%@ page import="java.util.*" %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>登录页面</title>
</head>
<body>
<form name="loginForm" method="post" action="judgeUser.jsp">
<table>
<tr>
<td>用户名：<input type="text" name="userName" id="userName" /></td>
</tr>
<tr>
<td>密码：<input type="password" name="password" id="password" /></td>
</tr>
<tr>
<td>
<input type="submit" value="登录" style="background-color:pink" />
<input type="reset" value="重置" style="background-color:red" />
</td>
</tr>
</table>
</form>
</body>
</html>
2. judge.jsp 文件
<%@ page language="java" contentType="text/html; charset=GB18030" pageEncoding="GB18030"%>
<%@ page import="java.util.*" %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>身份验证</title>
</head>
<body>
<%
request.setCharacterEncoding("GB18030");
String name = request.getParameter("userName");
String password = request.getParameter("password");
if (name.equals("abc") && password.equals("123")) {
%>
<jsp:forward page="afterLogin.jsp">
<jsp:param name="userName" value="<%=name%>" />
</jsp:forward>
<%
} else {
%>
<jsp:forward page="login.jsp" />
<%
}
%>
</body>
</html>
3. afterLogin.jsp 文件
<%@ page language="java" contentType="text/html; charset=GB18030" pageEncoding="GB18030"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>登录成功</title>
</head>
<body>
<%
request.setCharacterEncoding("GB18030");
String name = request.getParameter("userName");
out.println("欢迎你：" + name);
%>
</body>
</html>
扩展资料：Java Web 登录界面源代码
1. Data_uil.java 文件
import java.sql.*;
public class Data_uil {
public Connection getConnection() {
try {
Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
String user = "***";
String password = "***";
String url = "jdbc:sqlserver://127.0.0.1:1433;DatabaseName=***";
Connection con = null;
try {
con = DriverManager.getConnection(url, user, password);
} catch (SQLException e) {
e.printStackTrace();
}
return con;
}
public String selectPassword(String username) {
Connection connection = getConnection();
String sql = "select * from login where username=?";
PreparedStatement preparedStatement = null;
ResultSet result = null;
String password = null;
try {
preparedStatement = connection.prepareStatement(sql);
preparedStatement.setString(1, username);
result = preparedStatement.executeQuery();
if (result.next())
password = result.getString("password");
} catch (SQLException e) {
e.printStackTrace();
} finally {
close(preparedStatement);
close(result);
close(connection);
}
System.out.println("找到的数据库密码为：" + password);
return password;
}
public void close(Connection con) {
try {
if (con != null) {
con.close();
}
} catch (SQLException e) {
e.printStackTrace();
}
}
public void close(PreparedStatement preparedStatement) {
try {
if (preparedStatement != null) {
preparedStatement.close();
}
} catch (SQLException e) {
e.printStackTrace();
}
}
public void close(ResultSet resultSet) {
try {
if (resultSet != null) {
resultSet.close();
}
} catch (SQLException e) {
e.printStackTrace();
}
}
}
2. login_check.jsp 文件
<%@ page language="java" contentType="text/html; charset=utf-8" pageEncoding="utf-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>验证用户密码</title>
</head>
<body>
<jsp:useBean id="util" class="util.Data_uil" scope="page" />
<%
String username = (String) request.getParameter("username");
String password = (String) request.getParameter("password");
if (username == null || "".equals(username)) {
out.print("<script language='javaScript'>alert('用户名不能为空');</script>");
response.setHeader("refresh", "0;url=user_login.jsp");
} else {
System.out.println("输入的用户名:" + username);
String passwordInDataBase = util.selectPassword(username);
System.out.println("密码：" + passwordInDataBase);
if (passwordInDataBase == null || "".equals(passwordInDataBase)) {
out.print("<script language='javaScript'>alert('用户名不存在');</script>");
response.setHeader("refresh", "0;url=user_login.jsp");
} else if (passwordInDataBase.equals(password)) {
out.print("<script language='javaScript'>alert('登录成功');</script>");
response.setHeader("refresh", "0;url=loginSucces.jsp");
} else {
out.print("<script language='javaScript'>alert('密码错误');</script>");
response.setHeader("refresh", "0;url=user_login.jsp");
}
}
%>
</body>
</html>
3. loginSucces.jsp 文件
<%@ page language="java" contentType="text/html; charset=utf-8" pageEncoding="utf-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1" />
<title>Insert title here</title>
</head>
<body>
<hr size="10" width="26%" align="left" color="green" />
<font size="6" color="red">登录成功</font>
<hr size="10" width="26%" align="left" color="green" />
</body>
</html>
4. user_login.jsp 文件
<%@ page language="java" contentType="text/html; charset=utf-8" pageEncoding="utf-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1" />
<title>登录界面</title>
</head>
<body background="C:\Users\win8\workspace\Login\image\9dcbdc339e72a5663b5c289fb5573c13_10.jpg">
<center>
<br><br><br><br><br><br>
<h1 style="color:yellow">Login</h1>
<br>
<form name="loginForm" action="login_check.jsp" method="post">
<table Border="0">
<tr>
<td>账号</td>
<td><input type="text" name="username" /></td>
</tr>
<tr>
<td>密码</td>
<td><input type="password" name="password" /></td>
</tr>
</table>
<br>
<input type="submit" value="登录" style="color:#BC8F8F" />
</form>
</center>
</body>
</html>
